In 1989 Kozinn and Scott published what were at the time the ideal
indications for Partial Knee Replacement1. According to
their criteria, only 5% of patients were candidates for PKR. This may
partly explain why there is low utilisation of PKA today, with it only
being used for 8%2,3 of knee replacements worldwide.

An intact, functioning ACL plays a critical role in determining
candidacy for PKA.

One study showed that 47.6% of all knee replacement patients
are candidates for PKA4

In a study of
consecutive TKAs by Lee et al.5 61% of patients
were found to have an intact ACL

In a more recent
presentation, Berend, et al.6 found 53% of knee
replacement candidates had a normal, intact ACL

Utilisation: closing the revision gap

The revision gap between PKA and TKA reported in national joint
registries has been reduced with increased utilisation of PKRs:

Tregonning, et al in a study reviewing the New Zealand Joint
Registry found that surgeons performing at least 12 PKRs per year
are found to have a decreased revision rate7

Liddle, AD. et al8 found in the National Joint
Registry for England and Wales that surgeons utilising PKA for at
least 20% of their annual knee replacements experienced a dramatic
decrease in their revision rate

What's more, with research showing that up to 61% of
patients5 could be candidates for PKA, the optimal usage of
performing at least 12 partial knee replacements per
year7 can easily be achieved.